Investigating the Effects of HMGB1 Overexpression on Colorectal Cancer Cell Migration via Oncolytic Herpes simplex Virus Type 1 (oHSV-1)

Background

Colorectal Cancer (CRC) represents a significant global health challenge, and its progression, resistance to therapy, and metastasis are strongly influenced by the tumor microenvironment, including factors like hypoxia. This study explores the impact of High Mobility Group Box 1 (HMGB1) overexpression on CRC cell migration, while identifying potential genes associated with this process.

Methods

To explore this, we developed oncolytic virotherapy, resulting in HSVHMGB1, an oncolytic Herpes simplex virus that expresses HMGB1. HMGB1 is known its role in cancer progression, particularly in the context of cancer cell migration.

Results

Contrary to expectations, our scratch assays indicated that HSV-HMGB1 did not significantly induce migration in CRC cells, suggesting that HMGB1 might not directly contribute to this process. Employing microarray analysis, we investigated gene expression changes linked to CRC cell migration, leading to construction of a Protein-Protein Interaction (PPI) network. This network revealed the presence of hub proteins, including as NDRG1, LGALS1, and ANGPTL4, which are recognized for their roles in cancer cell migration. The differential expression of these genes under hypoxic conditions was further validated using quantitative RT-PCR, aligning with the findings from our microarray data.

Conclusion

Our findings emphasize the complex regulation of CRC cell migration, and provides valuable insights into potential molecular mechanisms and pathways. These findings have implications for further research into cancer progression and the development of therapeutic strategies.

Structure-based evaluation of the envelope domain III-nonstructural protein 1 (EDIII-NS1) fusion as a dengue virus vaccine candidate

The lack of effective medicines or vaccines, combined with climate change and other environmental factors, annually subjects a significant proportion of the world's inhabitants to the risk of dengue virus (DENV) infection. These conditions increase the likelihood of exposure to mosquito-borne diseases such as dengue fever. Hence, many research approaches tend to develop efficient vaccine candidates against the dengue virus. Therefore, we used immunoinformatics and bioinformatics to design a construction for developing a candidate vaccine against dengue virus serotypes. In this study, the in silico structure, containing the non-structural protein 1 region (NS1) (consensus and epitope), the envelope domain III protein (EDIII) as the structural part of the virus construction, and the bc-loop of envelope domain II (EDII) as the neutralizing and protected epitope, were employed. We utilized in silico tools to enhance the immunogenicity and effectiveness of dengue virus vaccine candidates. Evaluations included refining and validating physicochemical characteristics, B and T-cell epitopes, homology modeling, and the three-dimensional structure to assess the designed vaccine's quality. In silico results for tertiary structure prediction and validation revealed high-quality modeling for all vaccine constructs. Additionally, the instructed model demonstrated stability throughout molecular dynamics simulation. The results of the immune simulation suggested that the titers of IgG and IgM could be raised to desirable values following injection into in vivo models. It can be concluded that the designed construct effectively induce humoral and cellular immunity and can be proposed as effective vaccine candidate against four dengue serotypes.Communicated by Ramaswamy H. Sarma.

The chicken chorioallantoic membrane model for isolation of CRISPR/cas9-based HSV-1 mutant expressing tumor suppressor p53

Oncolytic viruses (OVs) have emerged as a novel cancer treatment modality, which selectively target and kill cancer cells while sparing normal ones. Among them, engineered Herpes simplex virus type 1 (HSV-1) has been proposed as a potential treatment for cancer and was moved to phase III clinical trials. Previous studies showed that design of OV therapy combined with p53 gene therapy increases the anti-cancer activities of OVs. Here, the UL39 gene of the ICP34.5 deleted HSV-1 was manipulated with the insertion of the EGFP-p53 expression cassette utilizing CRISPR/ Cas9 editing approach to enhance oncoselectivity and oncotoxicity capabilities. The ΔUL39/Δγ34.5/HSV1-p53 mutant was isolated using the chorioallantoic membrane (CAM) of fertilized chicken eggs as a complementing membrane to support the growth of the viruses with gene deficiencies. Comparing phenotypic features of ΔUL39/Δγ34.5/HSV1-p53-infected cells with the parent Δγ34.5/HSV-1 in vitro revealed that HSV-1-P53 had cytolytic ability in various cell lines from different origin with different p53 expression rates. Altogether, data presented here illustrate the feasibility of exploiting CAM model as a promising strategy for isolating recombinant viruses such as CRISPR/Cas9 mediated HSV-1-P53 mutant with less virus replication in cell lines due to increased cell mortality induced by exogenous p53.

Bacterial production and biophysical characterization of a hard-to-fold scFv against myeloid leukemia cell surface marker, IL-1RAP

BACKGROUND

Interleukin-1 receptor accessory protein (IL-1RAP) is one of the most promising therapeutic targets proposed for myeloid leukemia. Antibodies (Abs) specific to IL-1RAP could be valuable tools for targeted therapy of this lethal malignancy. This study is about the preparation of a difficult-to-produce single-chain variable fragment (scFv) construct against the membrane-bound isoform of human IL-1RAP using Escherichia coli (E. coli).

METHODS

Different approaches were examined for refolding and characterization of the scFv. Binding activities of antibody fragments were comparatively evaluated using cell-based enzyme-linked immunosorbent assay (ELISA). Homogeneity and secondary structure of selected scFv preparation were analyzed using analytical size exclusion chromatography (SEC) and circular dichroism (CD) spectroscopy, respectively. The activity of the selected preparation was evaluated after long-term storage, repeated freeze-thaw cycles, or following incubation with normal and leukemic serum.

RESULTS

Strategies for soluble expression of the scFv failed. Even with the help of Trx, ≥ 98% of proteins were expressed as inclusion bodies (IBs). Among three different refolding methods, the highest recovery rate was obtained from the dilution method (11.2%). Trx-tag substantially enhanced the expression level (18%, considering the molecular weight (MW) differences), recovery rate (˃1.6-fold), and binding activity (˃2.6-fold increase in absorbance450nm). The produced scFv exhibited expected secondary structure as well as acceptable bio-functionality, homogeneity, and stability.

CONCLUSION

We were able to produce  21 mg/L culture functional and stable anti-IL-1RAP scFv via recovering IBs by pulse dilution procedure. The produced scFv as a useful targeting agent could be used in scheming new therapeutics or diagnostics for myeloid malignancies.

Looking for biomarkers in interferon response pathway to predict response to oncolytic HSV-1 in breast cancer: An ex vivo study

Breast cancer is the most common malignancy in women worldwide. Administration of oncolytic viruses is one of the novel promising cancer therapy approaches. Replication of these viruses is usually limited to cancer cells that have interferon (IFN) signaling defects. However, Interferon signaling is not completely impaired in all cancer cells which may limit the benefits of virotherapy.    Identification of realistic IFN-mediated biomarkers to identify patients who most likely respond to virotherapy would be helpful. In this study, eight patients-derived primary tumor cultures were infected with an ICP34.5 deleted oHSV, then the rate of infectivity, cell survival, and expression of the gene involved in IFN pathway were analyzed.Data showed that mRNA expressions of Myeloid differentiation primary response protein (Myd88) is significantly higher in tumors whose primary cultures showed less cell death and resistance to oHSV infectivity (P-value < 0.05). The differentiating cut off of Myd88 expression, inferred from the receiver operating characteristic (ROC) curve, predicted that only 13 out of 16 other patients could be sensitive to this oHSV. Identifying such biomarker improves our ability to select the patients who do not exhibit resistance to virotherapy.

Fiber manipulation and post-assembly nanobody conjugation for adenoviral vector retargeting through SpyTag-SpyCatcher protein ligation

For adenoviruses (Ads) to be optimally effective in cancer theranostics, they need to be retargeted toward target cells and lose their natural tropism. Typically, this is accomplished by either engineering fiber proteins and/or employing bispecific adapters, capable of bonding Ad fibers and tumor antigen receptors. This study aimed to present a simple and versatile method for generating Ad-based bionanoparticles specific to target cells, using the SpyTag-SpyCatcher system. The SpyTag peptide was inserted into the HI loop of fiber-knob protein, which could act as a covalent anchoring site for a targeting moiety fused to a truncated SpyCatcher (SpyCatcherΔ) pair. After confirming the presence and functionality of SpyTag on the Ad type-5 (Ad5) fiber knob, an adapter molecule, comprising of SpyCatcherΔ fused to an anti-vascular endothelial growth factor receptor 2 (VEGFR2) nanobody, was recombinantly expressed in Escherichia coli and purified before conjugation to fiber-modified Ad5 (fmAd5). After evaluating fmAd5 detargeting from its primary coxsackie and adenovirus receptor (CAR), the nanobody-decorated fmAd5 could be efficiently retargeted to VEGFR2-expressing 293/KDR and human umbilical vein endothelial (HUVEC) cell lines. In conclusion, a plug-and-play platform was described in this study for detargeting and retargeting Ad5 through the SpyTag-SpyCatcher system, which could be potentially applied to generate tailored bionanoparticles for a broad range of specific targets; therefore, it can be introduced as a promising approach in cancer nanotheranostics.

Modifying oncolytic virotherapy to overcome the barrier of the hypoxic tumor microenvironment. Where do we stand?

Viruses are completely dependent on host cell machinery for their reproduction. As a result, factors that influence the state of cells, such as signaling pathways and gene expression, could determine the outcome of viral pathogenicity. One of the important factors influencing cells or the outcome of viral infection is the level of oxygen. Recently, oncolytic virotherapy has attracted attention as a promising approach to improving cancer treatment. However, it was shown that tumor cells are mostly less oxygenated compared with their normal counterparts, which might affect the outcome of oncolytic virotherapy. Therefore, knowing how oncolytic viruses could cope with stressful environments, particularly hypoxic environments, might be essential for improving oncolytic virotherapy.

Genomic and serological assessment of asymptomatic severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) infections in child labor

Since working children have limited access to testing and monitoring for COVID-19, we decided to measure SARS-CoV-2 prevalence among them and compare it to non-working children. Our objective is to compare the frequency of SARS-CoV-2 genome and anti-SARS-CoV-2 antibody among working and non-working children. Volunteer child labor studying at Defense of Child Labor and Street Children and randomly selected 5-18-year-old (same range as child labor group) unemployed children participated in this study. The groups, respectively, had 65 and 137 members. This is an analytical cross-sectional study that surveys molecular prevalence of SARS-CoV-2 infection by RT-PCR, and seroprevalence of SARS-CoV-2 antibody by ELISA in working and non-working children. The IBM SPSS statistics software version 25 was used for data analysis. The χ2 or Fisher's exact test was used to analyze categorical dependent variables, for calculating odds ratios and 95% confidence intervals. Among the children enrolled in this study, molecular prevalence of SARS-CoV-2 turned out to be 18.5% in working children while it was 5.8% in unemployed children [aOR: 3.00 (CI95%: 1.00-7.00); P value: 0.003] and seroprevalence turned out to be 20% in working children vs 13.9% in non-working children [aOR: 1.000 (CI95%: 0.00-2.00); > P 0.001]. Equal SARS-CoV-2 viral load as adults and no symptoms or mild ones in children, coupled with working children's strong presence in crowded areas and their higher rate of COVID-19 prevalence, make them a probable source for spread of the virus.

Adenovirus vector-based vaccines as forefront approaches in fighting the battle against flaviviruses

Flaviviruses are arthropod-borne viruses (arboviruses) that have been recently considered among the significant public health problems in defined geographical regions. In this line, there have been vaccines approved for some flaviviruses including dengue virus (DENV), Japanese encephalitis virus (JEV), yellow fever virus (YFV), and tick-borne encephalitis virus (TBEV), although the efficiency of such vaccines thought to be questionable. Surprisingly, there are no effective vaccine for many other hazardous flaviviruses, including West Nile and Zika viruses. Furthermore, in spite of approved vaccines for some flaviviruses, for example DENV, alternative prophylactic vaccines seem to be still needed for the protection of a broader population, and it originates from the unsatisfying safety, and the efficacy of vaccines that have been introduced. Thus, adenovirus vector-based vaccine candidates are suggested to be effective, safe, and reliable. Interestingly, recent widespread use of adenovirus vector-based vaccines for the COVID-19 pandemic have highlighted the importance and feasibility of their widespread application. In this review, the applicability of adenovirus vector-based vaccines, as promising approaches to harness the diseases caused by Flaviviruses, is discussed.

Screening of candidate genes associated with high titer production of oncolytic measles virus based on systems biology approach

The number of viral particles required for oncolytic activity of measles virus (MV) can be more than a million times greater than the reported amount for vaccination. The aim of the current study is to find potential genes and signaling pathways that may be involved in the high-titer production of MV. In this study, a systems biology approach was considered including collection of gene expression profiles from the Gene Expression Omnibus (GEO) database, obtaining differentially expressed genes (DEGs), performing gene ontology, functional enrichment analyses, and topological analyses on the protein-protein interaction (PPI) network. Then, to validate the in-silico data, total RNA was isolated from five cell lines, and full-length cDNA from template RNA was synthesized. Subsequently, quantitative reverse transcription-PCR (RT-qPCR) was employed. We identified five hub genes, including RAC1, HSP90AA1, DNM1, LTBP1, and FSTL1 associated with the enhancement in MV titer. Pathway analysis indicated enrichment in PI3K-Akt signaling pathway, axon guidance, proteoglycans in cancer, regulation of actin cytoskeleton, focal adhesion, and calcium signaling pathways. Upon verification by RT-qPCR, the relative expression of candidate genes was generally consistent with our bioinformatics analysis. Hub genes and signaling pathways may be involved in understanding the pathological mechanisms by which measles virus manipulates host factors in order to facilitate its replication. RAC1, HSP90AA1, DNM1, LTBP1, and FSTL1 genes, in combination with genetic engineering techniques, will allow the direct design of high-throughput cell lines to answer the required amounts for the oncolytic activity of MV.

Cell type-specific response of colon cancer tumor cell lines to oncolytic HSV-1 virotherapy in hypoxia

Background

Novel strategies are required since the hypoxic tumor microenvironment is one of the important impediments for conventional cancer therapy. High mobility group box 1 (HMGB1) protein can block aerobic respiration in cancer cells. We hypothesized that HMGB1could also kill the colorectal cancer cells during hypoxia.

Methods

In this study, we developed oncolytic herpes simplex virus type 1 expressing HMGB1 protein (HSV-HMGB1) and investigated the cytotoxic effect of HSV-HMGB1 and its parental virus (HSV-ble) on three colorectal cancer cells (HCT116, SW480, and HT29) under normoxic (20% oxygen) and hypoxic (1% oxygen) conditions. We further identified potential autophagy- related genes in HT29 cells by retrieving mRNA expression microarray datasets from the Gene Expression Omnibus database. These genes were then detected in HT29 cells infected with HSV-HMGB1 and HSV-ble during normoxia and hypoxia by Real-Time quantitative PCR (qRT-PCR).

Results

The cytotoxic effect of HSV-HMGB1 was significantly higher than that of HSV-ble during normoxia; however, during hypoxia, HSV-HMGB1 enhanced the viability of HT29 cells at MOI 0.1. Analyzing the cell death pathway revealed that HSV-HMGB1 induced autophagy in HT29 cells under hypoxic conditions.

Conclusion

In conclusion, it appears that oncolytic virotherapy is cell context-dependent. Therefore, understanding the cancer cells’ characteristics, microenvironment, and cell signaling are essential to improve the therapeutic strategies.

Supplementary Information

The online version contains supplementary material available at 10.1186/s12935-022-02564-4.

Adjuvant Effects of Pseudomonas aeruginosa Flagellin on the Immunological Patterns of the HIV-1 Vaccine Candidate: Vaccine Formulations Versus Different Routes of Immunization

New strategies to increase the immune response to HIV-1 vaccine using immunological adjuvants such as Toll-like receptor agonists are needed. In this study, HIV-1 p24-Nef and conjugated form of the vaccine candidate to type-A flagellin (FLA) were injected in the BALB/c mice in different routes. Two weeks after the last immunization, lymphocyte proliferation was measured by the BrdU method. The IL-4 and IFN-γ levels, as well as the total IgG antibody and its isotypes titer, were evaluated by the enzyme-linked immunosorbent assay method. The IFN-γ ELISPOT was also performed. Our data showed that the HIV-1 p24-Nef alone and conjugated to type-A flagellin (FLA) significantly increased lymphocyte proliferation responses as well as higher levels of cytokines and IFN-γ producing lymphocytes and the level of humoral immune responses compared with the control groups. The cell-mediated immune responses through the subcutaneous route and humoral immune responses through the intramuscular route were significantly higher in the conjugated form than in the mere vaccine candidate. In conclusion, when the FLA as an adjuvant is constructed in the HIV-1 vaccine candidate, it could effectively improve both humoral and cellular immune responses. Furthermore, modification in the vaccine formulation could change the optimal route of vaccine inoculation.

The ins and outs of SARS-CoV-2 variants of concern (VOCs)

SARS-CoV-2, a newly emerging coronavirus that caused the COVID-19 epidemic, has been spreading quickly throughout the world. Despite immunization and some fairly effective therapeutic regimens, SARS-CoV-2 has been ravaging patients, health workers, and the economy. SARS-CoV-2 mutates and evolves to adapt to its host as a result of extreme selection pressure. As a consequence, new SARS-CoV-2 variants have emerged, some of which are classified as variants of concern (VOC) because they exhibit greater transmissibility, cause more-severe disease, are better able to escape immunity, or cause higher mortality than the original Wuhan strain. Here, we introduce these VOCs and review their characteristics, such as transmissibility, immune escape, mortality risk, and diagnostics.

Oncolytic herpes simplex virus type-1 expressing IL-12 efficiently replicates and kills human colorectal cancer cells

An increasing attitude towards oncolytic viruses (OVs) is witnessed following T-VEC's approval. In this study, we aimed to delete ICP47 and insert IL-12 in the ICP34.5 deleted HSV-1 backbone to improve the oncolytic properties and provide an immune-stimulatory effect respectively. The wild-type and recombinant viruses infected both cancerous, SW480 and HCT116, and non-cancerous, HUVEC, cell lines. Green-red Δ47/Δ34.5 was constructed by replacing ICP47 with GFP. Both ICP34.5 copies were replaced by hIL12. Cytotoxicity and growth kinetics of Δ47/Δ34.5/IL12 and Δ47/Δ34.5 were comparable to the wild virus in the cancerous cells. Δ47/Δ34.5/IL12 was able to produce IL12 in the infected cell lines. INF-γ production and PBMC proliferation were observed in the PBMCs treated with the lysate of Δ47/Δ34.5/IL12 infected cells. These results demonstrated that Δ47/Δ34.5/IL12 was competent in taking advantage of the cytotoxic effect of HSV-1 plus immune-stimulatory characteristics of IL-12.

Activating Natural Killer Cell Receptors, Selectins, and Inhibitory Siglecs Recognize Ebolavirus Glycoprotein

Expression of the extensively glycosylated Ebolavirus glycoprotein (EBOV-GP) induces physical alterations of surface molecules and plays a crucial role in viral pathogenicity. Here we investigate the interactions of EBOV-GP with host surface molecules using purified EBOV-GP, EBOV-GP-transfected cell lines, and EBOV-GP-pseudotyped lentiviral particles. Subsequently, we wanted to examine which receptors are involved in this recognition by binding studies to cells transfected with the EBOV-GP as well as to recombinant soluble EBOV-GP. As the viral components can also bind to inhibitory receptors of immune cells (e.g., Siglecs, TIM-1), they can even suppress the activity of immune effector cells. Our data show that natural killer (NK) cell receptors NKp44 and NKp46, selectins (CD62E/P/L), the host factors DC-SIGNR/DC-SIGN, and inhibitory Siglecs function as receptors for EBOV-GP. Our results show also moderate to strong avidity of homing receptors (P-, L-, and E-selectin) and DC-SIGNR/DC-SIGN to purified EBOV-GP, to cells transfected with EBOV-GP, as well as to the envelope of a pseudotyped lentiviral vector carrying the EBOV-GP. The concomitant activation and inhibition of the immune system exemplifies the evolutionary antagonism between the immune system and pathogens. Altogether these interactions with activating and inhibitory receptors result in a reduced NK cell-mediated lysis of EBOV-GP-expressing cells. Modulation of these interactions may provide new strategies for treating infections caused by this virus.

Novel G-CSF conjugated anionic globular dendrimer: Preparation and biological activity assessment

The most crucial role of granulocyte colony-stimulating factor (G-CSF) in the body is to increase the strength of immune system. In recent years, research on the use of nanoparticles in pharmaceuticals has been considered, most of which have been for drug-loading purposes. In this study, a novel G-CSF conjugated dendrimer was synthesized and characterized using different techniques. In vitro cytotoxicity was assessed on A549 and L929 cells, while abnormal toxicity was studied in mice. In vitro and in vivo biological activities were assessed in NFS60 cells and rats, respectively. In addition, in vivo distribution, plasma half-life, and histopathological effect were studied in rat. The characterization tests confirmed the successful conjugation. There was no difference between G-CSF cytotoxicity before and after conjugation, and no difference with the control group. No mice showed abnormal toxicity. Although in vitro biological activity revealed both conjugated and free G-CSF promote proliferation cells, biological activity decreased significantly after conjugation about one-third of the unconjugated form. Nonetheless, in vivo biological activity of conjugated G-CSF increased by more than 2.5-fold relative to the unconjugated form, totally. Fortunately, no histopathologic adverse effect was observed in vital rat tissues. Also, in vivo distribution of the conjugate was similar to the native protein with an enhanced terminal half-life. Our data revealed that G-CSF conjugated dendrimer could be considered as a candidate to improve the in vivo biological activity of G-CSF. Moreover, multivalent capability of the dendrimer may be used for other new potentials of G-CSF in future perspectives.

Prevalence of COVID-19 in Iran: results of the first survey of the Iranian COVID-19 Serological Surveillance programme

Objectives

This study aims to estimate the prevalence of coronavirus disease 2019 (COVID-19) in the general population of Iran.

Methods

The target population was all Iranian people aged 6 years and older in the country. A stratified random sampling design was used to select 28 314 people from among the individuals registered in the electronic health record systems used in primary health care in Iran. Venous blood was taken from each participant and tested for the IgG antibody against COVID-19. The prevalence of COVID-19 was estimated at provincial and national levels after adjusting for the measurement error of the laboratory test, non-response bias and sampling design.

Results

Of the 28 314 Iranians selected, 11 256 (39.75%) participated in the study. Of these, 5406 (48.0%) were male and 6851 (60.9%) lived in urban areas. The mean (standard deviation) participant age was 35.89 (18.61) years. The adjusted prevalence of COVID-19 until 20 August 2020 was estimated as 14.2% (95% uncertainty interval 13.3%–15.2%), which was equal to 11 958 346 (95% CI 11 211 011–12 746 776) individuals. The adjusted prevalences of infection were 14.6%, 13.8%, 16.6%, 11.7% and 19.4% among men, women, urban population, rural population and individuals aged 60 years or more, respectively. Ardabil, Golestan and Khuzestan provinces had the highest prevalence and Alborz, Hormozgan and Kerman provinces had the lowest.

Conclusions

Based on the study results, a large proportion of the Iranian population had not yet been infected by COVID-19. The observance of hygienic principles and social restrictions should therefore continue until the majority of the population has been vaccinated.

Bi/tri-specific antibodies (HN-Fc-CD16 and HN-Fc-IL-15-CD16) cross-linking natural killer (NK)-CD16 and Newcastle Disease Virus (NDV)-HN, enhanced NK activation for cancer immunotherapy

Cancer/tumor cells infected with the "avian paramyxovirus Newcastle Disease Virus (TC-NDV)" express the viral hemagglutinin-neuraminidase (HN) on the cell surface that is used as both the danger signal and anchor for bi/tri-specific antibodies (bs/tsAbs).We constructed a bs-Ab (HN-Fc-CD16) that bindsto HN and natural killer (NK)-CD16 receptor (FcgRIII)and a ts-Ab (HN-Fc-IL15-CD16) harbouring NK-activating cytokine "IL-15" within the bs-Ab.In silicoand computational predictions indicated proper exposure of both Abs in bs/tsAbs.Properbinding of thebi/tsAbstoHN on surface of TC-NDVandCD16⁺-cells was demonstrated by flow cytometry.The bi/tsAbstriggeredspecificcytotoxicity of NK cells againstTC-NDVand elicited substantial IFN-γproduction by activated NK cells(higher for ts-Ab) that sound promising for cancer immunotherapy purposes.

Nationwide population-based surveys of Iranian COVID-19 Serological Surveillance (ICS) program: The surveys protocol

Background: Serological surveillance of COVID-19 through conducting repetitive population-based surveys can be useful in estimating and monitoring changes in the prevalence of infection across the country. This paper presents the protocol of nationwide population-based surveys of the Iranian COVID-19 Serological Surveillance (ICS) program. Methods: The target population of the surveys is all individuals ≥6 years in Iran. Stratified random sampling will be used to select participants from those registered in the primary health care electronic record systems in Iran. The strata are the 31 provinces of the country, in which sampling will be done through simple random sampling. The sample size is estimated 858 individuals for each province (except for Tehran province, which is 2574) at the first survey. It will be recalculated for the next surveys based on the findings of the first survey. The participants will be invited by the community health workers to the safe blood sampling centers at the district level. After obtaining written informed consent, 10 mL of venous blood will be taken from the participants. The blood samples will be transferred to selected reference laboratories in order to test IgG and IgM antibodies against COVID-19 using an Iranian SARS-CoV-2 ELISA Kit (Pishtaz Teb). A serologically positive test is defined as a positive IgG, IgM, or both. After adjusting for the measurement error of the laboratory test, nonresponse bias, and sampling design, the prevalence of COVID-19 will be estimated at the provincial and national levels. Also, the approximate incidence rate of infection will be calculated based on the data of both consecutive surveys. Conclusion: The implementation of these surveys will provide a comprehensive and clear picture of the magnitude of COVID-19 infection and its trend over time for health policymakers at the national and subnational levels.

Severe acute respiratory syndrome-coronavirus-2 spike (S) protein based vaccine candidates: State of the art and future prospects

Coronavirus disease 2019 (Covid-19) is caused by severe acute respiratory syndrome-coronavirus-2 (SARS-CoV-2) which is responsible for a global pandemic that started in late 2019 in Wuhan, China. To prevent the worldwide spread of this highly pathogenic virus, development of an effective and safe vaccine is urgently needed. The SARS-CoV-2 and SARS-CoV share a high degree of genetic and pathologic identity and share safety and immune-enhancement concerns regarding vaccine development. Prior animal studies with first generation (whole virus-based) preparations of SARS-CoV vaccines (inactivated and attenuated vaccine modalities) indicated the possibility of increased infectivity or eosinophilic infiltration by immunization. Therefore, development of second and third generation safer vaccines (by using modern vaccine platforms) is actively sought for this viral infection. The spike (S) protein of SARS-CoVs is the main determinant of cell entry and tropism and is responsible for facilitating zoonosis into humans and sustained person-to-person transmission. Furthermore, 'S' protein contains multiple neutralizing epitopes that play an essential role in the induction of neutralizing antibodies (nAbs) and protective immunity. Moreover, T-cell responses against the SARS-CoV-2 'S' protein have also been characterized that correlate to the IgG and IgA antibody titres in Covid-19 patients. Thus, S protein is an obvious candidate antigen for inclusion into vaccine platforms against SARS-CoV-2 viral infection. This manuscript reviews different characteristics of S protein, its potency and 'state of the art' of the vaccine development strategies and platforms using this antigen, for construction of a safe and effective SARS-CoV-2 vaccine.

The Inclusive Review on SARS-CoV-2 Biology, Epidemiology, Diagnosis, and Potential Management Options

A novel coronavirus member was reported in Wuhan City, Hubei Province, China, at the end of the year 2019. Initially, the infection spread locally, affecting the Wuhan people, and then expanded rapidly throughout the world. On 11 March 2020, the World Health Organization (WHO) proclaimed it a global pandemic. The virus is a new strain most closely related to a bat coronavirus (RaTG13) which was not previously discovered in humans and is now formally known as the severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2). Coronavirus disease 2019 (COVID-19) is the disease syndrome that the SARS-CoV-2 virus triggers. It is suggested that SARS-CoV-2 can be transmitted through aerosols, direct/indirect contact, and also during medical procedures and specimen handling. The infection is characterized by isolated flu-like symptoms, but there may be specific signs of fever, fatigue, cough, and shortness of breath, as well as the loss of smell and breathing difficulty. Within this report, we tried to review the most current scientific literature published by January 2021 on various aspects of the outbreak, including virus structure, pathogenesis, clinical presentation, epidemiology, diagnostic approaches, potential therapeutics and vaccines, and prospects. We hope this article makes a beneficial impact on public education to better deal with the SARS-CoV-2 crisis and push a step forward in the near term towards its prevention and control.

Lentiviral Expression of Rabies Virus Glycoprotein in the Rat Hippocampus Strengthens Synaptic Plasticity

Rabies virus (RABV) is a neurotropic virus exclusively infecting neurons in the central nervous system. RABV encodes five proteins. Among them, the viral glycoprotein (RVG) plays a key role in viral entry into neurons and rabies pathogenesis. It was shown that the nature of the C-terminus of the RABV G protein, which possesses a PDZ-binding motif (PBM), modulates the virulence of the RABV strain. The neuronal protein partners recruited by this PBM may alter host cell function. This study was conducted to investigate the effect of RVG on synaptic function in the hippocampal dentate gyrus (DG) of rat. Two μl (10⁸ T.U./ml) of the lentiviral vector containing RVG gene was injected into the DG of rat hippocampus. After 2 weeks, the rat's brain was cross-sectioned and RVG-expressing cells were detected by fluorescent microscopy. Hippocampal synaptic activity of the infected rats was then examined by recording the local field potentials from DG after stimulation of the perforant pathway. Short-term synaptic plasticity was also assessed by double pulse stimulation. Expression of RVG in DG increased long-term potentiation population spikes (LTP-PS), whereas no facilitation of LTP-PS was found in neurons expressing δRVG (deleted PBM). Furthermore, RVG and δRVG strengthened paired-pulse facilitation. Heterosynaptic long-term depression (LTD) in the DG was significantly blocked in RVG-expressing group compared to the control group. This blockade was dependent to PBM motif as rats expressing δRVG in the DG-expressed LTD comparable to the RVG group. Our data demonstrate that RVG expression facilitates both short- and long-term synaptic plasticity in the DG indicating that it may involve both pre- and postsynaptic mechanisms to alter synaptic function. Further studies are needed to elucidate the underlying mechanisms.

In-silico identification of new inhibitors for Low-density lipoprotein receptor-related protein6 (LRP6)

Low-density lipoprotein receptor-related protein 6 (LRP6) is an important therapeutic target for diseases such as osteoporosis, Alzheimer, cancer, and neurodegenerative disease. Computational methods such as ligand-based and structure-based virtual screening have been introduced as an extremely efficient and accurate tool for finding new drug targets and candidates. In this study, we aimed to screen the National Cancer Institute (NCI) Diversity Set II and parts of the ZINC database by virtual screening to identify potential and safe compounds that can inhibit the LRP6 protein. By utilizing various screening methods such as rigid and flexible molecular docking and Lipinski's rule of five, we identified 10 potential compounds. Then, their validity was further tested by molecular dynamics simulation and MMPBSA binding free energy calculations. Eventually, it was concluded that ZINC03954520, ZINC01729523, ZINC03898665, ZINC13152226, ZINC26730911 and ZINC01069082 compounds can be potential drug compounds for inhibiting LRP6 protein. These compounds in complex with β-propeller domains of LRP6 showed that they are capable of altering the backbone of these domains and interfere with their structural dynamics which may lead to the inhibition of the signal transmission. Communicated by Ramaswamy H. Sarma.

Expression and Purification of a Bispecific Antibody against CD16 and Hemagglutinin Neuraminidase (HN) in E. Coli for Cancer Immunotherapy

Background

: Immunotherapy of cancer by bispecific antibodies (bsAb) is an attractive approach for retargeting immune effector cells including natural killer (NK) cells to the tumor if the proper expression and purification of the bsAb for such applications could be addressed. Herein, we describe E. coli expression of a recombinant bsAb (bsHN-CD16) recognizing NK-CD16 and hemagglutinin neuraminidase (HN) of Newcastle Disease Virus (NDV). This bsAb might be efficient for ex vivo stimulation of NK cells via coupling to HN on the surface of the NDV-infected tumor cells.

Methods

A bsAb-encoding pcDNA3.1 vector (anti-HN scFv-Fc-anti-CD16 scFv) was used as a template, and the scFv segments (after enzymatic digestion and cutting of the Fc part) were rejoined to construct the Fc-deprived bsAb (anti-HN scFv-anti-CD16 scFv; bsHN-CD16). The constructed bsHN-CD16 was inserted into the HindIII and BamHI site of the T7 promoter-based pET28a plasmid. Following restriction analyses and DNA sequencing to confirm the cloning steps, bsHN-CD16 encoding pET28a was transformed into the E. coli (Rosetta DE3 strain), induced for protein expression by IPTG, and the protein was purified under native condition by Ni/NTA column using imidazole.

Results

Analyses by SDS-PAGE and Western Blotting using Rabbit anti-human whole IgG-HRP conjugate, confirmed the expression and purification of the bsAb with the expected full size of 55 kDa and yields around 8% of the total protein.

Conclusion

Results showed efficient production of the bsAb in E. coli for future large-scale purification.

Efficient production of a lentiviral system for displaying Crimean-Congo hemorrhagic fever virus glycoproteins reveals a broad range of cellular susceptibility and neutralization ability

Crimean-Congo hemorrhagic fever (CCHF) is a tick-borne disease with a mortality rate of up to 50% in humans. To avoid safety concerns associated with the use of live virus in virus neutralization assays and to detect human serum neutralizing antibodies, we prepared lentiviral particles containing the CCHF glycoprotein (lenti-CCHFV-GP). Incorporation of the GP into the lentiviral particle was confirmed by electron microscopy and Western blotting. Lenti-CCHFV-GP was found to be able to infect a wide range of cell lines, including BHK-21, HeLa, HepG2, and AsPC-1 cells. In addition, lenti-CCHFV-GP was successfully used as an alternative to CCHFV for the detection of neutralizing antibodies. Sera collected from CCHF survivors neutralized lenti-CCHFV-GP particles in a dose-dependent manner. Our results suggest that the lenti-CCHFV-GP pseudovirus can be used as a safe tool for neutralization assays in low-containment laboratories.

The Implication of Androgens in the Presence of Protein Kinase C to Repair Alzheimer’s Disease-Induced Cognitive Dysfunction

Aging, as a major risk factor of memory deficiency, affects neural signaling pathways in hippocampus. In particular, age-dependent androgens deficiency causes cognitive impairments. Several enzymes like PKC are involved in memory deficiency. Indeed, PKC regulatory process mediates α-secretase activation to cleave APP in β-amyloid cascade and tau proteins phosphorylation mechanism. Androgens and cortisol regulate PKC signaling pathways, affecting the modulation of RACK1. Mitogen-activated protein kinase/ERK signaling pathway depends on CREB activity in hippocampal neurons and is involved in regulatory processes via PKC and androgens. Therefore, testosterone and PKC contribute in the neuronal apoptosis. The present review summarizes the current status of androgens, PKC, and their influence on cognitive learning. Inconsistencies in experimental investigations related to this fundamental correlation are also discussed, with emphasis on the mentioned contributors as the probable potent candidates for learning and memory improvement.

The Implication of Androgens in the Presence of Protein Kinase C to Repair Alzheimer’s Disease-Induced Cognitive Dysfunction

Aging, as a major risk factor of memory deficiency, affects neural signaling pathways in hippocampus. In particular, age-dependent androgens deficiency causes cognitive impairments. Several enzymes like protein kinase C (PKC) are involved in memory deficiency. Indeed, PKC regulatory process mediates α-secretase activation to cleave APP in β-amyloid cascade and tau proteins phosphorylation mechanism. Androgens and cortisol regulate PKC signaling pathways, affecting the modulation of receptor for activated C kinase 1. Mitogen-activated protein kinase/ERK signaling pathway depends on CREB activity in hippocampal neurons and is involved in regulatory processes via PKC and androgens. Therefore, testosterone and PKC contribute in the neuronal apoptosis. The present review summarizes the current status of androgens, PKC, and their influence on cognitive learning. Inconsistencies in experimental investigations related to this fundamental correlation are also discussed, with emphasis on the mentioned contributors as the probable potent candidates for learning and memory improvement.

Detection and molecular characterization of bovine leukemia virus in various regions of Iran

Purpose. Bovine leukemia virus (BLV) infects cattle worldwide, imposing an economic impact on the dairy cattle industry. The purpose of this study was to evaluate the molecular epidemiology of BLV in Iran.Methodology. Blood samples taken from 280 cows aged over 2 years old from 13 provinces of Iran were used for leukocyte count and blocking ELISA. Genomic DNA was extracted from the peripheral blood leukocytes of BLV-infected samples and fetal lamb kidney cells to perform PCR of partial env, rex and tax genes and long-terminal-repeat region. The PCR products were sequenced, the phylogenetic tree of each gene was constructed, and nucleotide and amino acid sequence pair distances were calculated.Results. The frequency of BLV infection was 32.8 % among animals and was 80 % among provinces. In BLV seropositive animals, the rate of persistent lymphocytosis was 36.9 %. The constructed phylogenetic trees showed the presence of two BLV genotypes (1 and 4) in Iranian strains. As previous studies, our results showed that the env gene was more variable than previously thought, the Rex protein could withstand more amino acid changes compared to the Tax protein, and no significant differences were observed in average changes of the nucleotide of these genes between clinical stages.Conclusions. Our data indicates an increase in the frequency of this infection in Iran. This is the first study report of the presence of BLV genotype 4 in Iranian farms. These findings may have an important role in the control and prevention of BLV infection in Iran and other countries.

Generation of CCR5-ablated Human Induced Pluripotent Stem Cells as a Therapeutic Approach for Immune-mediated Diseases

C-C chemokine receptor type 5 (CCR5) is a receptor for some pro-inflammatory chemokines which plays important roles in immunological disorder and host responses to infectious agents. Additionally, the prognosis of some immune-mediated diseases in the people who are naturally carrying the CCR5 32bp deletions is optimistic. However, the clinical application of CCR5 32bp mutant cells is very limited due to the rare availability of donors who are homozygous for CCR5 D32. The transfection efficiency of nucleofected placental mesenchymal stem cells derived - human induced pluripotent stem cells (PMSC-hiPSCs) was examined through the evaluation of green fluorescent protein (GFP) expression using flow cytometry. The nucleofected clonal populations were selected using colony picking. The CCR5 gene disrupted clonal populations were evaluated and confirmed by PCR and Sanger sequencing methods. Also, off-target sites were evaluated by the "Loss of a primer binding site" technique. The results of the flow cytometry revealed that among the six applied nucleofection programs for PMSC-iPSCs, the program of A-033 has achieved the best transfection efficiency (27.7%). PCR and then sequencing results confirmed the CCR5 gene was disrupted in two clonal populations of 16 (D6) and 62 (D20) by the Clustered regularly interspaced short palindromic repeats/CRISPR associated nuclease 9 (CRISPR/Cas9) system. The "Loss of a primer binding site" technique showed that no exonic off-target mutations were induced in both CCR5 gene disrupted clonal populations. We establish a CRISPR/Cas9 mediated CCR5 ablated PMSC-hiPSCs without detectable off-target damage. This approach can provide a stable supply of autologous/allogeneic CCR5-disrupted PMSC-hiPSCs that might be a feasible approach for the treatment of immune-mediated diseases.

Using chemical chaperones to increase recombinant human erythropoietin secretion in CHO cell line

In recombinant protein production, over-expressed genes induce unfolded protein response (UPR), overloaded protein aggregation in endoplasmic reticulum and its expansion. In this study, we have used 16 chemicals to improve erythropoietin production in engineered CHO cells and tried to study the mechanism of reducing protein aggregation in each treatment. Endoplasmic reticulum expansion was studied through endoplasmic reticulum specific labeling with utilizing fluorescent glibenclamide and its molecular chaperones expression were studied by real-time polymerase chain reaction. The increase in the mRNA level of EPO and endoplasmic reticulum chaperones GRP78/BiP, XBP1, ATF6, and ATF4 in different chemical treatments were not related to ER expansion. On the other hand, ER expansion in beta alanine, beta cyclodextrin and taurine treatments resulted in increased EPO secretion. Dramatically increase in EPO expression in conjugated linoleic acid, spermidine, trehalose, and maltose (19, 20, 16, and 19-fold, respectively) did not increase erythropoietin productivity, but betaine which did not caused ER expansion, with minor increase in EPO gene expression increase EPO productivity. The results indicated that betaine increase EPO secretion in engineered CHO cell line without relation to ER expansion and molecular chaperones expression.

Evaluation of first rapid diagnostic kit for Anti-Crimean-Congo Hemorrhagic Fever virus IgM antibody using clinical samples from Iran

Crimean-Congo Hemorrhagic Fever (CCHF) is a potentially fatal tick-borne viral disease, which is in the WHO list for emerging infections likely to cause major epidemics in the near future. Early diagnosis of CCHF is very important for both patient treatment and infection control. An efficient CCHF rapid test therefore is of great significance. This study was conducted to evaluate the sensitivity and specificity of the first CCHF rapid diagnostic kit (CCHF Sero K-SeT, CORIS BioConcept, Belgium) for detection of IgM specific antibody in patients' sera or plasma, using 87 clinical serum samples from Iranian patients. Although the assay showed an acceptable specificity of 92.9% (13/14), a low sensitivity rate of 39.7% (29/73) was observed. There was no association between the results of CCHF rapid diagnostic kit and the genotype of CCHF virus. This evaluation revealed that the CCHF Sero K-SeT is not suitable for screening of CCHF suspected cases due to its poor sensitivity.

Therapeutic potency of oncolytic virotherapy-induced cancer stem cells targeting in brain tumors, current status, and perspectives

Brain tumors are the most common form of solid tumors in children and is presently a serious therapeutic challenge worldwide. Traditional treatment with chemotherapy and radiotherapy was shown to be unsuccessful in targeting brain tumor cancer stem cells (CSCs), leading to recurrent, treatment-resistant secondary malignancies. Oncolytic virotherapy (OV) is an effective antitumor therapeutic strategy which offers a novel, targeted approach for eradicating pediatric brain tumor CSCs by utilizing mechanisms of cell killing that differ from conventional therapies. A number of studies and some clinical trials have therefore investigated the effects of combined therapy of radiations or chemotherapies with oncolytic viruses which provide new insights regarding the effectiveness and improvement of treatment responses for brain cancer patients. This review summarizes the current knowledge of the therapeutic potency of OVs-induced CSCs targeting in the treatment of brain tumors for a better understanding and hence a better management of this disease.

Therapeutic potency of oncolytic virotherapy in breast cancer targeting, current status and perspective

Breast cancer is the most common cause of cancer death in women and presents a serious therapeutic challenge worldwide. Traditional treatments are less successful at targeting cancer tumors, leading to recurrent treatment-resistant secondary malignancies. Oncolytic virotherapy (OV) is a novel anticancer strategy with therapeutic implications at targeting cancer cells by using mechanisms that differ from conventional therapies. Administration of OVs either alone or in combination with standard therapies provide new insights regarding the effectiveness and improvement of treatment responses for breast cancer patients. This review summarizes cellular, animal and clinical studies investigating therapeutic potency of oncolytic virotherapy in breast cancer treatment for a better understanding and hence a better management of this disease.

Collagen II-primed Foxp3 Transduced T Cells Ameliorate Collagen-induced Arthritis in Rats: The Effect of Antigenic Priming on T Regulatory Cell Function

Regulatory T cells (Tregs) play a major role in the prevention of autoimmune diseases. Transfer of Foxp3 gene into conventional T cells converts their phenotype to regulatory T cells. Therefore, the question arises as to whether adoptively transferred in vitro differentiated Treg cells specific for a locally expressed antigen might have better inhibitory effects on the progression of the disease as compared with antigen-nonspecific T reg cells. Herein, we investigated the therapeutic potential of primed and unprimed retrovirus mediated Foxp3-overexpression T cells following intravenously injected of these cells into affected rats with collagen-induced arthritis (CIA), an animal model of rheumatoid arthritis. Our analyses demonstrate that systemic administration of collagen II primed Foxp3-transduced T cells could markedly ameliorate CIA inflammatory responses at clinical (p<0.0014) and pathological exchanges including cellular infiltration (p=0.002), bone erosion (p=0.0013) and synovial hyperplasia (p=0.002). In contrast, collagen II unprimed Foxp3-transduced T cells like as collagen II primed or unprimed GFP-transduced T cells did not reveal any beneficial effects on arthritis features as compared with untreated group (p>0.05). Therefore, we believe that collagen II primed Foxp3-transduced T cells are interacting locally and systemically with immune cells which reveled with decreasing of T cells infiltration into joints along with specific CII IgG production. Considering the results described here, it appears that the using patients' T cells which previously exposed to specific antigens may have more effective therapeutic advantage in the production of induced regulatory T cells in the treatment of arthritis.

New synergistic combinations of differentiation-inducing agents in the treatment of acute promyelocytic leukemia cells

Acute promyelocytic leukemia (APL) was considered to be one of the most lethal forms of leukemia in adults before the introduction of the vitamin A metabolite all-trans retinoic acid (ATRA). Surprisingly, it has been confirmed that FICZ (6-Formylindolo (3, 2-b) carbazole) enhances ATRA-induced differentiation. Moreover, a number of studies have demonstrated that anti CD44 monoclonal antibody (mAb) induces to bring back differentiation blockage the leukemic stem cells. The level of differentiation markers including CD11b and CD11c in NB4 cells was assessed by flow cytometry. The induction of apoptosis was also evaluated. We estimated the induction potential of a triple compound of ATRA-FICZ, anti-CD44 maps. The cells showed the gradually increased expression levels of CD11b and CD11c. A mixture of a "CD44 mAb, ATRA and FICZ effectively promoted granulocytic maturation resulting in increased rates of apoptosis. The differences in expression of CD11b and CD11c at 5 μg/ml and 10 μg/ml were significant. These phenomena were highest at 10 μg/ml CD44 mAb concentrations. Synergistic induction differentiation and apoptosis of APL cells by using a co-treatment with novel triple compound are more effective for eradicating blasts and controlling the metastasis. Our results show that the addition of anti-CD44 mAb improves "ATRA-FICZ"-induced differentiation and has potential to reduce usual chemotherapy based treatments. Taken together, this compound may lead to novel clinical applications of differentiation-based approaches for APL and other types of leukemia. Further clinical studies would be recommended to clarify the clinical efficacy.

Prophylactic DNA vaccine targeting Foxp3+ regulatory T cells depletes myeloid-derived suppressor cells and improves anti-melanoma immune responses in a murine model

Regulatory T cells (Treg) and myeloid-derived suppressor cells (MDSC) are the two important and interactive immunosuppressive components of the tumor microenvironment that hamper anti-tumor immune responses. Therefore, targeting these two populations together might be beneficial for overcoming immune suppression in the tumor microenvironment. We have recently shown that prophylactic Foxp3 DNA/recombinant protein vaccine (Foxp3 vaccine) promotes immunity against Treg in tumor-free conditions. In the present study, we investigated the immune modulatory effects of a prophylactic regimen of the redesigned Foxp3 vaccine in the B16F10 melanoma model. Our results indicate that Foxp3 vaccination continuously reduces Treg population in both the tumor site and the spleen. Surprisingly, Treg reduction was associated with a significant decrease in the frequency of MDSC, both in the spleen and in the tumor environment. Furthermore, Foxp3 vaccination resulted in a significant reduction of arginase-1(Arg-1)-induced nitric oxide synthase (iNOS), reactive oxygen species (ROS) and suppressed MDSC activity. Moreover, this concurrent depletion restored production of inflammatory cytokine IFN-γ and enhanced tumor-specific CTL response, which subsequently resulted in the reduction of tumor growth and the improved survival rate of vaccinated mice. In conclusion, our results revealed that Foxp3 vaccine promotes an immune response against tumor by targeting both Treg and MDSC, which could be exploited as a potential immunotherapy approach.

Physicochemical screening for chemical stabilizer of erythropoietin to prevent its aggregation

Recombinant protein aggregation is a problematic issue and can provoke immunological response. The aim of this study was to analyze the stability of erythropoietin (EPO), as a therapeutic protein expressed in mammalian cells, in the presence of different chemicals and find a specific stabilizer for EPO. The effects of several chemicals, including mannitol, betaine, trehalose, taurine, linoleic acid, beta-cyclodextrin, copper sulfate, spermidine, maltose, maltodextrin, sucrose, dextran, beta-alanine, myo-inositol, and cysteine, on protein stabilization through the thermally induced aggregation of EPO were monitored. Based on the results of turbidity assay for thermal aggregation, three different patterns were observed for protein stability of active pharmaceutical ingredient of EPO, namely, accelerated, dose-dependent, and inhibitory behaviors for aggregate formation due to treatment with spermidine, mannitol, and betaine, respectively. According to circular dichroism outcomes, EPO treatment with betaine and spermidine resulted in different helical contents of the secondary structure. Dynamic light scattering experiments indicated that treating EPO with betaine resulted in less protein aggregation due to freeze and thaw stresses. Betaine was able to stabilize EPO and inhibit its aggregation, as opposed to spermidine that induced protein aggregation.

Correction to: Prevalence of HIV-1 transmitted drug resistance in recently infected, treatment-naïve persons in the Southwest of Iran, 2014-2015

The author would like to correct the error in the online published article. The correct details are given below for your reading.

CRF35-AD as the Main Circulating Genotype of Human Immunodeficiency Virus Type 1 Infection in Iran: A Phylogenetic and Demographic-Based Study

Finding the predominant circulating subtype of human immunodeficiency virus type 1 (HIV-1) and surveying co-infection with other infectious viruses are crucial to making preventive decisions. To this end, 50 Iranian HIV-positive patients made up of 37 men and 13 women were selected. Most of the HIV-positive patients (70%) were intravenous drug users (IDUs), and 48 and 32% of patients were co-infected with HCV and HBV, respectively. The rate of simultaneous infection with HIV, HCV, and HBV was found to be 6%. The p17 region of the gag and the c2-v5 region of the env genes were sequenced and then clustered by phylogenetic analyses. CRF35-AD was specified as the predominant circulating subtype among different high-risk groups. In our survey, most of the patients in the IDU group had co-infections with HCV and HBV. Some possible reasons for the increased transmission risk of HIV in IDUs could be low levels of education, poor hygiene and housing conditions, and limited access to health services.

Immunization of mice by a multimeric L2-based linear epitope (17-36) from HPV type 16/18 induced cross reactive neutralizing antibodies

Current licensed and commercially available prophylactic human papillomavirus (HPV) vaccines (Cervarix and quadrivalent/nine valents Gardasil) are based on major capsid protein L1 virus-like particles (VLPs) production which are expensive and type specific. Minor capsid L2-RG1 linear epitope (17-36) is a known candidate for induction of cross-neutralizing antibodies to develop low-cost pan-HPV vaccines. Herein, we report construction and expression of a three tandem repeats of L2-RG1 derived from HPV16 and 18 fused with the same head to tail pattern (HPV16:17-36×3+ HPV18:17-36×3; hereafter termed dual-type fusion L2 peptide) in E. coli and provide the results of its immunogenicity in mice. SDS-PAGE and western blot analyses indicated proper expression of the peptide that could be further purified by Ni-NTA affinity chromatography via the located C-terminal 6xHis-tag. Mice immunized by formulation of the purified peptide and Freund adjuvant raised neutralizing antibodies which showed proper cross reactivity to HPV L2 (11-200) of types: 18, 16, 31 and 45 (which totally are responsible for 90% of cervical cancers) and efficiently neutralized HPV18/16 pseudoviruses in vitro. Our results imply the possibility of development of a simple, low-cost preventive HPV vaccine based on this dual-type fusion L2 peptide in bacterial expression system with broad spectrum.

[Translational efficiency of BVDV IRES and EMCV IRES for T7 RNA polymerase driven cytoplasmic expression in mammalian cell lines]

Mammalian T7 polymerase-based cytoplasmic expression systems are common tool for molecular studies. The majority of these systems include the internal ribosome entry site (IRES) of the encephalomyocarditis virus (EMCV). To carry out a cap-independent translation process, this type of IRES might require the expression of an extensive array of host factors, what is a disadvantage. Other IRESes might be less dependent on the host cell factors, but their biology is characterized to a lesser degree. Here, we compare the translational efficiencies of bovine viral diarrhea virus (BVDV) IRES with that of ECMV. Both IRESes were tested in reporter vectors containing the T7 promoter, an IRES of choice and the coding sequence of the enhanced green fluorescent protein (EGFP). To provide for the expression of T7 RNA polymerase, the corresponding gene was isolated from Escherichia coli and inserted into pCDNA3.1-Hygro(+). After co-transfection of the T7 RNA polymerase encoding vector with either of the two IRES-containing reporter vectors into T7 baby hamster kidney (T7-BHK), human embryonic kidney (HEK) 293T, chinese hamster ovary (CHO) and HeLa cells, the translational efficiency of the reporter construct was studied by fluorescence microscopy and flow cytometry. In T7-BHK, HEK 293T and HeLa cells the translational efficiency of BVDV IRES was two to three times higher than that of EMCV IRES. In CHO cells, BVDV IRES and EMCV IRES were equally efficient. An analysis of the secondary structure of respective mRNAs showed that their ΔG values were -544.00 and -469.40 kcal/mol for EMCV IRES and BVDV IRES harboring molecules, respectively. As EMCV IRES-containing mRNA is more stable, it is evident that other, still unidentified factors should be held responsible for the enhanced translational efficiency of BDVD IRES. Taken together, our results indicate the potential of BVDV IRES as a replacement for EMCV IRES, which is now commonly used for T7 polymerase driven cytoplasmic expression of genes of interest or virus cDNA rescue experiments.

Molecular epidemiology of infectious diseases

Molecular epidemiology (ME) is a branch of epidemiology developed by merging molecular biology into epidemiological studies. In this paper, the authors try to discuss the ways that molecular epidemiology studies identify infectious diseases' causation and pathogenesis, and unravel infectious agents' sources, reservoirs, circulation pattern, transmission pattern, transmission probability, and transmission order. They bring real-world examples of research works in each area to make each study design more understandable. They also address some research areas and study design aspects that need further attention in future. They close with some thoughts about future directions in this field and emphasize on the need for training competent molecular epidemiology specialists that are capable of dealing with rapid advances in the field.

MiR-377 reverses cancerous phenotypes of pancreatic cells via suppressing DNMT1 and demethylating tumor suppressor genes

AIM

The aim was to investigate the effect of miR-377 on DNMT1 expression and cancer phenotype in pancreatic cancer cells.

MATERIALS & METHODS

Real-time PCR, luciferase assay, MTT and Annexin-PI staining were used.

RESULTS

Decreased miR-377 and increased DNMT1 (verified as a target for mir-377) levels in pancreatic cancer tissues and cell lines in comparison with normal tissues was confirmed to be influenced by promoter methylation. Also hypermethylation of BNIP3, SPARC, TFPI2 and PENK promoters was observed in tumor samples but not in normal tissues which negatively correlated with their expression. Restoration of miR-377 resulted in a reduction of the expression of DNMT1 and reactivation of BNIP3 and SPARC genes via promoter demethylation. Furthermore, enhanced expression of miR-377 could significantly inhibit cell proliferation and induce apoptosis.

CONCLUSION

Our findings showed that miR-377 through targeting DNMT1 could reduce DNA methylation of some tumor suppressor genes and restore their expression in pancreatic cancer cells.